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Bahia-class cruiser
|module2= Gardiner and Gray eds. (1984), p. 405 | Ship length = oa pp | Ship beam = | Ship draft = forward amidships aft | Ship propulsion = Five Parsons steam turbines,Janes Fighting Ships (2001) 1919, p. 300 ten Yarrow boilers Coal normal Maximum | Ship speed = as designed trial at full load | Ship endurance = @ @ | Ship complement = 320 to 357 | Ship armament = ten × /50 caliber, six × /50 caliber, two × torpedo tubes | Ship armor = Deck: Conning tower: | Ship notes = These specifications apply to when Bahia was commissioned. }} }} The Bahia class was a pair of scout cruisers built for Brazil by Armstrong Whitworth in the United Kingdom, based on a design that borrowed heavily from the British scout cruisers. The class comprised the lead ship and her sister , along with a canceled third ship, Ceara."The Brazilian Navy," Times (London), 28 December 1908, 48f. Both were named after states of Brazil. As a class, they were the fastest cruisers in the world when commissioned, and the first in the Brazilian Navy to use steam turbines for propulsion. In the mid-1920s, both ships were extensively modernized with three new Brown–Curtis turbine engines and six new Thornycroft boilers, and, in the process, was converted from coal-burning ships to oil-burning. The refit resulted in a striking aesthetic change, with the exhaust being trunked into three funnels, instead of two. The armament was also modified; three Madsen guns, a Hotchkiss machine gun, and four torpedo tubes were added. In the Second World War, both were used as convoy escorts. On 4 July 1945, the Bahia was lost after an accident caused a massive explosion which incapacitated the ship and sunk her within minutes, resulting a large loss of life. The Rio Grande do Sul survived the war and was scrapped in 1948. Design The class's design borrowed heavily from the British scout cruisers. The ships displaced , and their dimensions were overall, between perpendiculars, at the beam, and a draft of forward, amidships, and aft. They were powered by five Parsons steam turbines, and ten Yarrow boilers, with a coal bunker that could hold a normal load of , and a maximum load of . The Bahia class was designed to reach a speed of ; both ships exceeded this during trials with the Bahia reaching at trial. As designed, the class's range was at , or at . The class was armed with ten /50 caliber, six QF 3 pounder /50 caliber guns and two torpedo tubes. The class was lightly armored with only of deck armor, with the conning tower having . Construction The class was part of a large 1904 naval building program by Brazil. Gardiner and Gray eds. (1984), p. 403 Also planned as part of this were the two dreadnoughts, ten s, three submarines and a submarine tender.Scheina (2003), p. 37 With a design that borrowed heavily from the British scout cruisers, Bahia s keel was laid first on 19 August 1907 in Armstrong Whitworth's Elswick, Newcastle upon Tyne yard, followed by Rio Grande do Sul 30 August 1907. Construction took about a year and a half, and both ships were launched in 1909. s launching date as 20 January 1909, and her sister ship Rio Grande do Sul s as 20 April 1909. Conway's All the World's Fighting Ships 1906–1921 and the Brazilian Navy's official history reverse these dates, giving 20 January for Rio Grande do Sul and 20 April for Bahia. This article uses the former date because of Miramar s use of builders' records, which, in this case, should be the most accurate source. See: ; ; Gardiner and Gray eds. (1984), p. 405; }} Both ships were completed and commissioned into the navy in 1910. As a class, Bahia and Rio Grande do Sul were the fastest cruisers in the world when they were commissioned, and the first in the Brazilian Navy to utilize steam turbines for propulsion. Modernization In the mid-1920s, the class underwent significant modernization. The original five turbines were replaced by three Brown–Curtiss turbines, while the original ten boilers were replaced by six Thornycroft oil-burning boilers, which necessitated the addition of a third funnel. The former coal bunkers, along with some of the space freed up by the decrease in boilers, were converted to hold of oil. These changes resulted in Bahia s top speed increasing to . All of the boats onboard were replaced, and three Madsen guns, a Hotchkiss machine gun, and four torpedo tubes were added to give the ship a defense against aircraft and more power against surface ships. The class was modernized again twice during World War II, in both 1942 and 1944. The modernizations were not as extensively as it was in the 1920s; the Brazilian Navy's official history of the Bahia reports these but does not specify what modifications the ship underwent in which year. Two guns were replaced with L/23 AA guns, Madsen guns were replaced with seven Oerlikon 20 mm cannons in single mounts, and a director for these guns was installed. Two depth charge tracks were added, improved range-finders were added to the guns, and sonar and radar were fitted, in addition to other minor modifications. Loss of the Bahia On 4 July 1945, Bahia was acting as a plane guard for transport aircraft flying from the Atlantic to Pacific theaters of war. While Bahia s gunners were firing at a kite for anti-aircraft practice, one fired too low and hit depth charges stored near the stern of the ship. A massive explosion incapacitated the ship and sunk her within minutes, resulting a large loss of life.Scheina (2003), p. 427 Notes Footnotes References * * * Bahia-class cruisers Category:Armstrong Whitworth ships Category:Tyne-built ships Category:1909 ships Category:World War I cruisers of Brazil Category:World War II cruisers of Brazil